Portable devices for data collection at locations remote from central facilities are now commonly available and becoming common place. These devices include hand-held units and lap-top computers. Hand-held data collection devices typically run dedicated, often single-function applications, which are pre-programmed for specific end uses in specific fields, e.g., traffic citations and inventory taking. Usually data is entered into the hand-held device by bar code readers or keyboards, or a combination of the two. While data entry by bar code reader can be effected swiftly, keyboard data entry frequently bogs down due to the lack of operator skill and the need to enter the data on a letter-by-letter and number-by-number, basis.
Furthermore, typical hand-held devices have limited display screen sizes and limited operating programs. They utilize small memories, read only memory ("ROM") and/or random access memory ("RAM"), in which the collected data is stored until it can be uploaded to a host computer by direct cable connection or modem. The specific application which the hand-held unit is to run typically is stored on-board in ROM.
On the other hand, lap-top computers typically are general-purpose machines which are not application-dedicated. Frequently, lap top computers' display screens are full size or nearly full size, unlike the hand-held units, and usually flip up for use. Entry of information is generally performed using a keyboard which is provided integrally in the lap-top computer's housing or as a peripheral, although other peripheral input devices such as a mouse or touch screen can also be used. Because the lap-top is intended for use while supported on the user's lap, as the name imports, use of a mouse or touch screen is difficult to coordinate or even precarious. In addition, the typical lap top computer's physical characteristics, including its unsymmetrical dimensions, bulkiness, weight, and off-set center of gravity, make use of the lap-top computer unwieldingly in many instances.
For both hand-held devices and lap-top computers, the need to use a keyboard for entry of data is viewed by many would-be users as being laborious or tedious or requiring a skill they have not mastered. This is particularly true for those individuals who are not office workers and have little or no typing skills or who have little or no experience with computers. The computer keyboard can be an intimidating device for them, all the more so when confronted by the traditional typewriter-type QWERTY keyboards.
Also known are systems of point-of-sale ("POS") terminals for use for such diverse purposes as grocery check-out at supermarkets, inventory control, credit authorization or verification or electronic fund transfer. In such systems, the input terminals typically are off-line devices operating limited programs mainly for arithmetic operations, using a keyboard bar code reader or other data entry devices to capture the data for uploading to a central processing computer. Furthermore, such POS terminals typically are disposed for use at fixed locations and, consequently, do not afford the convenience of portability for many applications. For many applications, portability or even ambulatory use is more than a convenience--it is a necessity.